1. Field of the Invention
The present invention relates to a control method/system for sensing conditions indicative of a misadjusted master clutch in a fully or partially automated mechanical transmission system. Upon sensing the presence of such conditions, the vehicle operator will be notified, a maintenance request will be established and/or the vehicle drive line system will be operated in a fault-tolerant manner.
2. Description of the Prior Art
Semi-automatic and fully automatic mechanical transmission systems are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 4,361,060; 4,593,580; 4,648,290; 4,722,248; 5,038,627; 5,053,961; 5,105,357; 5,272,939; 5,337,868; 5,435,212; 5,439,428; 5,508,290; 5,509,867 and 5,569,115, the disclosures of which are incorporated herein by reference. Such systems often incorporated control logic for fault-sensing and/or fault-tolerant operation, as may be seen by reference to U.S. Pat. Nos. 4,849,899 and 4,899,279, the disclosures of which are incorporated herein by reference.
The prior art systems, as disclosed, were not totally satisfactory, as they did not incorporate means or a method for determining that the vehicle master clutch was misadjusted to an extent that did or threatened to degrade vehicle operation. By way of example, a significantly misadjusted master clutch, even in the disengaged condition, may cause sufficient drag on the transmission input shaft to render disengaging and engaging gears, especially the start-from-stop gears, difficult or impossible. Further, a significantly misadjusted master clutch may interfer with the operation of or damage an input shaft brake.